I came across some signals on ramps along Interstate 435 the other day. How do those things work? I’m not sure how to react to these things.

Here’s some advice from the folks at Kansas City Scout, which involves state transportation officials on both sides of the state line:
• Pull up to the white stop bar marking on the pavement, where a sign tells drivers to “Stop Here on Red.” Pavement sensors detect vehicles there. If a vehicle does not pull up to the stop bar, the light will not cycle from red to green because it does not sense a vehicle.
• Once at the stop bar, look at the lower of two signal heads. The top one is for approaching drivers.
• At two-lane ramps, pay attention to the signal designated for your lane. If a motorist is in the right lane, observe the signal on the right. If a motorist is in the left lane, observe the signal on the left.
• Obey lane assignments and signs that designate “one car per green” or “two cars per green.” Otherwise, you could be cited for a traffic violation — on top of slowing down traffic flow.
• A “dark” signal means go. If yellow flashing beacons are not lit, and ramp meter signals are dark, do not stop on the ramp.